If the birds had been breeding, the scientists say that they would have found genetic "intermediates" - birds with genes from both species..."

"Researchers at Imperial College London and the University of Oxford have pioneered a new technique to see exactly how our body's "natural killer" white blood cells actually do their dirty work. It's the first time we've ever been able to see how this element of the body's natural defenses actually works.

There are myriad difficulties in trying to observe this kind of event. For one thing, the cells are incredibly small, and execute their, well, executions (that's an apt description, as you'll see) very, very quickly. Then there's the problem that the cells are three-dimensional (of course), while the high-speed microscopes used for this are only capable of seeing the horizontal plane. (3-D cameras are not, at the moment, quick enough to work for this.) Previously, researchers would have to painstakingly capture many 2-D images, then stack them on top of each other--not very efficient, and not particularly effective, either.

So how did these researchers pull it off? Says Professor Paul French of Imperial College London: "Using laser tweezers to manipulate the interface between live cells into a horizontal orientation means our microscope can take many images of the cell contact interface in rapid succession. This has provided an unprecedented means to directly see dynamic molecular processes that go on between live cells." But taking lots of images at once, the researchers can reconstruct a 3-D image with ease.

What's going on in that video above is essentially an execution. Inside the "natural killer" or "NK" cell, enzyme-filled granules organize, ready to stream out as soon as the cell creates a portal. Then, the granules attack the diseased cell. In this case, the NKs are using membrane nanotubes to pull them in, like a bungee cord.

NKs are used by the body to attack all kinds of damaged cells, from tumors to viruses, though they also sometimes attack transplanted organs. By understanding the intricacies of this operation, the scientists hope to create better medical treatments--they might use NK cells in medicine, or discover ways to stop them from attacking foreign but welcome tissue."

"The field of science is capable of some amazing things, mostly because it's filled with all the Albert Einsteins and Doogie Howsers the world has produced over the centuries. But it may shock you that some of the most mundane, everyday concepts are as big a mystery to scientists as they are to the average toddler.

Things like ..."

-- I was familiar with most of what this article had to say, it's definitely worth a read. Interesting that these are still mysteries.

"Stimulating a specific region of the brain leads to the production of new brain cells that enhance memory, according to an animal study in the September 21 issue of The Journal of Neuroscience. The findings show how deep brain stimulation (DBS) — a clinical intervention that delivers electrical pulses to targeted areas of the brain — may work to improve cognition.

"DBS has been quite effective for the treatment of movement disorders, such as Parkinson's disease, and has recently been explored for treatment of a range of neurologic and psychiatric conditions," said Paul Frankland, PhD, of The Hospital for Sick Children (SickKids), senior author of the study. "These new findings have important clinical implications as they inform potential treatments for humans with memory disorders."

Throughout life, new cells are born in parts of the hippocampus, the brain's learning and memory center. In the new study, Frankland and his colleagues found that one hour of electrical stimulation to the entorhinal cortex — a region that directly communicates with the hippocampus — in adult mice led to a two-fold increase in new cells in the hippocampus. Although the burst of new cells lasted for only about one week, the cells produced during this time window developed normally and made connections with other nearby brain cells.

Six weeks later, the researchers evaluated whether the newly integrated cells produced changes in memory. The authors tested how well the animals learned to navigate onto a landing submerged in a small pool of water. Compared with mice that did not receive the therapy, DBS mice spent more time swimming near the landing, suggesting that stimulation of the entorhinal cortex improved spatial learning.

"To date, the neurobiological basis for the clinical effect of DBS has not been well understood," said Daniel A. Peterson, PhD, of the Rosalind Franklin University of Medicine and Science, an expert on stem cells and brain repair who was unaffiliated with the study. "This study suggests that the stimulation of specific brain circuitry may result in the development of new functional brain cells in particular brain regions."

In a related preliminary study, researchers led by Andres Lozano, MD, PhD, of Toronto Western Hospital, recently published a Phase I clinical trial showing that DBS of the fornix, a brain region that also communicates directly with the hippocampus, slows cognitive decline in some people with dementia and other cognitive impairments. "The pro-cognitive effects of deep brain stimulation in human patients may result from the production of new neurons," Frankland said."

"The HEXAGON satellite spied on America’s Cold War foes for over a decade, taking extremely detailed (film!) photographs from space. It was 60 feet long—bigger than a bus. And the public never, ever saw it. We did.

To celebrate its 50th birthday, the top secret satellite operators at the National Reconnaissance Office gave the public a little present: full access to a real life HEXAGON at National Air and Space Museum’s Udvar-Hazy Center in Virginia — filled largely with nostalgic old spies and space engineers. So of course we checked it out. The enormity of the thing is stunning, as is its complexity.

In the 70s, flying a plane over the Soviet Union and China wasn’t like hopping on Jet Blue — especially one loaded with American spy gear. So the Pentagon cooked up HEXAGON — the most sophisticated space eyeball among the first generation of spy sats. Beginning in 1971, each HEXAGON was pushed up into space by a Titan III rocket, whereupon it would snap humungous panoramic views of Russian turf with its giant camera, which boasted a focal length of 77 inches, a 20-inch aperture, and the ability to capture detail down to two or three feet. But how’d it get the film down to Earth? With a lot of balls.

Each payload of recon negatives was launched in its own landing vehicle, met by a spy plane that would literally snatch it out of the air like a butterfly net. These photos were used to, of course, see what the dastardly commies were up to, and plan for an eventual war against them. Of course, none of this was ever needed, as they weren’t really up to that much. But the HEXAGON marked a profound shift for warfare — even cold warfare. For the first time, space was a battlefield. America began to think that to control space was to control what sat underneath it — the vacuum was militarized. And this giant hulk helped make it that way — a process that’ll never, ever be reversed."

While there were no injuries to the mother or daughter, the rabbit was not so lucky. The animal succumbed to smoke inhalation and did not survive, the fire department said."

"In the words of Mahatma Gandhi, "War makes people act like dicks." We don't want to glorify war or otherwise portray it as something other than terrible. Yet, war makes people think big, and sometimes you have to sit back and be amazed by what humans can accomplish when they really, really want to kill each other..."

"Sebastian Elser, Prof. Ben Moore and Dr. Joachim Stadel of the University of Zurich, Switzerland, in cooperation with Ryuji Morishima of NASA's Jet Propulsion Laboratory, tried to estimate how common Earth-Moon planetary systems are. They have found that 1 in 12 Earth-like planets probably hosts a Moon-like satellite. Since the Moon might have played an important role in the history of life on Earth, this estimate is important concerning the search for habitable planets.

Earth's Moon might have played an important role in the development and evolution of life on Earth. The Moon was formed via a giant impact in which a Mars-size projectile collided with the young Earth. The ejected material accumulated in orbit around our planet and formed the Moon. After its formation, the Moon was much closer to Earth than it is today, which caused high tides several times per day. This may have helped promote the very early evolution of life. In addition, a stable climate of more than a billion years may be essential to guarantee a suitable environment for life. But without its satellite, Earth would suffer chaotic variations of the direction of its spin axis, which would in turn result in dramatic variations of the climate.

Therefore, concerning the habitability of extrasolar planets, it is reasonable to ask: How common are Earth-Moon planetary systems? Sebastian Elser, Prof. Ben Moore and Dr. Joachim Stadel of the University of Zurich, Switzerland, along with Ryuji Morishima of NASA's Jet Propulsion Laboratory in Pasadena, California, ran a large set of N-body simulations to study the formation of the rocky planets in our solar system via the collisional growth of thousands of small rocky bodies in a disk around the Sun.

They identified numerous satellite-forming collisions during this process and estimated the masses of the generated companions. Moreover, they took into account the orbital evolution of the satellites, since tidal forces change the spin and orbit of a satellite and can cause it to be lost within a few thousand years in the most extreme cases.

Finally, they studied the subsequent collision history, since giant impacts after the epoch of satellite formation may pose a challenge to the survival of a satellite. They find that Earth-Moon planetary systems occur relatively frequently, with more than 1 in 12 terrestrial planets hosting a massive moon. Uncertainties in the study result in a range of 1 in 4 to 1 in 45. Further work and more N-body simulations are needed to obtain more precise results.

This work is being presented at the Extreme Solar Systems II conference in Jackson, Wyoming, and appears in the August 2011 issue of Icarus..."

"Demand for ginger-haired donors is so low that Cryos International says they needn't bother donating.

"There are too many redheads in relation to demand," Ole Schou, the director of Cryos, told the Danish newspaper, Ekstrabladet, according to London's Telegraph.

Men with scarlett manes sell "like hot cakes" in Ireland, Schou said, but that's about it.

"I do not think you choose a redhead, unless the partner - for example, the sterile male - has red hair, or because the lone woman has a preference for redheads," he said, the Telegraph reported. "And that's perhaps not so many, especially in the latter case."

Men with brown hair and brown eyes are very popular, Schou noted.

Cryos ships sperm to more than 65 countries around the world, and donors can score up to $500 for their semen..."

-- 'Cause no souls?

"It's been long known that asbestos spells trouble for human cells. Scientists have seen cells stabbed with spiky, long asbestos fibers, and the image is gory: Part of the fiber is protruding from the cell, like a quivering arrow that's found its mark.

But scientists had been unable to understand why cells would be interested in asbestos fibers and other materials at the nanoscale that are too long to be fully ingested. Now a group of researchers at Brown University explains what happens. Through molecular simulations and experiments, the team reports in Nature Nanotechnology that certain nanomaterials, such as carbon nanotubes, enter cells tip-first and almost always at a 90-degree angle. The orientation ends up fooling the cell; by taking in the rounded tip first, the cell mistakes the particle for a sphere, rather than a long cylinder. By the time the cell realizes the material is too long to be fully ingested, it's too late.

"It's as if we would eat a lollipop that's longer than us," said Huajian Gao, professor of engineering at Brown and the paper's corresponding author. "It would get stuck."

The research is important because nanomaterials like carbon nanotubes have promise in medicine, such as acting as vehicles to transport drugs to specific cells or to specific locations in the human body. If scientists can fully understand how nanomaterials interact with cells, then they can conceivably design products that help cells rather than harm them.

"If we can fully understand (nanomaterial-cell dynamics), we can make other tubes that can control how cells interact with nanomaterials and not be toxic," Gao said. "We ultimately want to stop the attraction between the nanotip and the cell."

Like asbestos fibers, commercially available carbon nanotubes and gold nanowires have rounded tips that often range from 10 to 100 nanometers in diameter. Size is important here; the diameter fits well within the cell's parameters for what it can handle. Brushing up against the nanotube, special proteins called receptors on the cell spring into action, clustering and bending the membrane wall to wrap the cell around the nanotube tip in a sequence that the authors call "tip recognition." As this occurs, the nanotube is tipped to a 90-degree angle, which reduces the amount of energy needed for the cell to engulf the particle..."

"Gamers have solved the structure of a retrovirus enzyme whose configuration had stumped scientists for more than a decade. The gamers achieved their discovery by playing Foldit, an online game that allows players to collaborate and compete in predicting the structure of protein molecules.

After scientists repeatedly failed to piece together the structure of a protein-cutting enzyme from an AIDS-like virus, they called in the Foldit players. The scientists challenged the gamers to produce an accurate model of the enzyme. They did it in only three weeks.

This class of enzymes, called retroviral proteases, has a critical role in how the AIDS virus matures and proliferates. Intensive research is under way to try to find anti-AIDS drugs that can block these enzymes, but efforts were hampered by not knowing exactly what the retroviral protease molecule looks like.

"We wanted to see if human intuition could succeed where automated methods had failed," said Dr. Firas Khatib of the University of Washington Department of Biochemistry. Khatib is a researcher in the protein structure lab of Dr. David Baker, professor of biochemistry.

Remarkably, the gamers generated models good enough for the researchers to refine and, within a few days, determine the enzyme's structure. Equally amazing, surfaces on the molecule stood out as likely targets for drugs to de-active the enzyme.

"These features provide exciting opportunities for the design of retroviral drugs, including AIDS drugs," wrote the authors of a paper appearing Sept. 18 in Nature Structural & Molecular Biology. The scientists and gamers are listed as co-authors.

This is the first instance that the researchers are aware of in which gamers solved a longstanding scientific problem.

Fold-it was created by computer scientists at the University of Washington Center for Game Science in collaboration with the Baker lab..."

"New University of Arizona research has discovered that seed beetles from the desert Southwest shelter their broods from attacking parasitic wasps under a stack of dummy eggs.

They lead modest lives among the palo verde, mesquite and acacia trees throughout the Southwestern U.S., laying their eggs on seed pods and defending the survival of their offspring against the parasitic wasp species that attacks their eggs before their young can develop.

They are the seed beetles Mimosestes amicus, living all around us in the trees of Tucson, and yet remaining all but invisible to our eyes – or nearly so.

Now, doctoral candidate Joseph Deas in the University of Arizona's Graduate Interdisciplinary Program in Entomology and Insect Science, along with his faculty advisor Martha Hunter in the department of entomology, is peering into their world through his microscope and has discovered something novel: The beetles, whose eggs frequently are parasitized by the wasp Uscana semifumipennis, have a strategy to protect their offspring that goes beyond a helpful habit.

"They're stacking their eggs in order to protect them from these parasitic wasps," said Deas, whose research appears in the Proceedings of the Royal Society B on Sept. 14.

The eggs have eyes

The wasps, called parasitoids because they kill their host rather than just taking advantage of its resources, deposit their own eggs inside the beetles'. The wasp larva gets a head start in life and develops before the beetle larva, hijacking the beetle egg yolk for its own nourishment.

"You can tell when an egg has been parasitized because the egg will start to darken and blacken," said Deas. "The beetle larva by that time will never form because all of the yolk is going inside the wasp larva. And then you can see little red eyes in there; the beetles don't have red eyes. It looks very evil."

As often happens in science, Deas came upon the discovery of M. amicus' strategy through the course of a different investigation..."

"Prominent scientists, including Sir David Attenborough and Richard Dawkins, have called on the government to toughen its guidance on the promotion of creationism in classrooms, accusing "religious fundamentalists" of portraying it as scientific theory in publicly funded schools.

Today's wireless-sensor networks can do everything from supervising factory machinery to tracking environmental pollution to measuring the movement of buildings and bridges. Working together, distributed sensors can monitor activity along an oil pipeline or throughout a forest, keeping track of multiple variables at a time.

While uses for wireless sensors are seemingly endless, there is one limiting factor to the technology — power. Even though improvements have brought their energy consumption down, wireless sensors’ batteries still need changing periodically. Especially for networks in remote locales, replacing batteries in thousands of sensors is a staggering task.

To get around the power constraint, researchers are harnessing electricity from low-power sources in the environment, such as vibrations from swaying bridges, humming machinery and rumbling foot traffic. Such natural energy sources could do away with the need for batteries, powering wireless sensors indefinitely.

Now researchers at MIT have designed a device the size of a U.S. quarter that harvests energy from low-frequency vibrations, such as those that might be felt along a pipeline or bridge. The tiny energy harvester — known technically as a microelectromechanical system, or MEMS — picks up a wider range of vibrations than current designs, and is able to generate 100 times the power of devices of similar size. The team published its results in the Aug. 23 online edition of Applied Physics Letters.

“There are wireless sensors widely available, but there is no supportive power package,” says Sang-Gook Kim, a professor of mechanical engineering at MIT and co-author of the paper. “I think our vibrational-energy harvesters are a solution for that.”

Putting the squeeze on

To harvest electricity from environmental vibrations, researchers have typically looked to piezoelectric materials such as quartz and other crystals. Such materials naturally accumulate electric charge in response to mechanical stress (piezo, in Greek, means to squeeze or press). In the past few years, researchers have exploited piezoelectric material, or PZT, at the microscale, engineering MEMS devices that generate small amounts of power..."

"Prominent scientists, including Sir David Attenborough and Richard Dawkins, have called on the government to toughen its guidance on the promotion of creationism in classrooms, accusing "religious fundamentalists" of portraying it as scientific theory in publicly funded schools.

A group of 30 scientists have signed a statement saying it is "unacceptable" to teach creationism and intelligent design, whether it happens in science lessons or not. The statement claims two organisations, Truth in Science and Creation Ministries International are "touring the UK and presenting themselves as scientists and their creationist views as science".

"Creationism and intelligent design are not scientific theories, but they are portrayed as scientific theories by some religious fundamentalists who attempt to have their views promoted in publicly funded schools," the scientists say.

"There should be enforceable statutory guidance that they may not be presented as scientific theories in any publicly funded school of whatever type."

The scientists claim organisations such as Truth in Science are encouraging teachers to incorporate intelligent design into their science teaching.

"Truth in Science has sent free resources to all secondary heads of science and to school librarians around the country that seek to undermine the theory of evolution and have intelligent design ideas portrayed as credible scientific viewpoints. Speakers from Creation Ministries International are touring the UK, presenting themselves as scientists and their creationist views as science at a number of schools."

Free schools and academies were not obliged to teach the national curriculum and so were "under no obligation to teach evolution at all," it added.

Truth in Science denied advocating the teaching of creationism in schools. "We wish to highlight the scientific weaknesses of neo-Darwinism and to encourage a more critical approach to the teaching of evolution in schools and universities," it said in a statement.

Creation Ministries International was unavailable for comment..."

"Life forms have been created that carry strands of genetic material designed and built from scratch in the lab, paving the way for on-demand "evolution" of organisms.

Scientists made sections of chromosomes, the long molecules that bear DNA, and transferred them into yeast cells, of the kind normally used in baking.

The cells adopted the new genetic code as part of their normal cellular machinery and, to the scientists' surprise, appeared as healthy as their natural counterparts.

The feat is a big step towards the manufacture of completely synthetic organisms that could be designed to churn out biofuels, vaccines and industrial chemicals, said Jef Boeke, who led the study at Johns Hopkins University in Maryland.

Studies of bugs with synthetic DNA are widely anticipated to shed light on some of the toughest questions in biology, such as what is the minimal suite of genes required for life on Earth.

"We have created a research tool that not only lets us learn more about yeast biology, but also holds out the possibility of someday designing genomes for specific purposes, like making new vaccines or medications," said Jef Boeke, who led the study at Johns Hopkins University in Maryland.

Built into the synthetic chromosomes are genetic sequences that, when triggered by a chemical, dramatically rearrange the organism's genes. The technique, known as genome scrambling, allows scientists to accelerate the evolution of the organisms on demand, by creating thousands of new strains and collecting the best survivors.

The advance was made possible by powerful techniques that have emerged from rapid developments in genetics, computing and synthetic chemistry.

Boeke's work centred on a yeast known as Saccharomyces cerevisiae, one of the most well-understood organisms in the field of genetics. It has 16 chromosomes that together carry around 6000 genes..."

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dmanlt.com has been online since 7.9.2010. It is a website about photography, science, art, technology, nature, culture, current events and everything in between and beyond. It is written and regularly updated by Donatas Urbonas.